JP4311777B2 - Method for producing graphite material - Google Patents
Method for producing graphite material Download PDFInfo
- Publication number
- JP4311777B2 JP4311777B2 JP19672098A JP19672098A JP4311777B2 JP 4311777 B2 JP4311777 B2 JP 4311777B2 JP 19672098 A JP19672098 A JP 19672098A JP 19672098 A JP19672098 A JP 19672098A JP 4311777 B2 JP4311777 B2 JP 4311777B2
- Authority
- JP
- Japan
- Prior art keywords
- raw material
- powder
- graphite material
- filler
- pulverized
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
Description
【０００１】
【産業上の利用分野】
本発明は、例えば放電加工用電極、半導体製造用のルツボ、単結晶引上げ装置用の部材、ＣＶＤ用サセプターなどとして好適な電気比抵抗や優れた熱伝導率などを備える高密度組織の等方性黒鉛材を製造する方法に関する。
【０００２】
【従来の技術】
等方性高密度黒鉛材は、放電加工用電極や半導体製造用のルツボ、連続鋳造用の鋳型等の素材として有用されているが、これら製品の耐久寿命は黒鉛材質の特性に支配される度合が大きいため従来から材質的な検討がなされている。
【０００３】
このような黒鉛材に対しては、かさ比重、電気比抵抗、曲げ強度、熱伝導率などの特性が問題となり、近時、この黒鉛材材質特性に対する要求は益々厳しくなってきている。
【０００４】
現在、一般に実用されている等方性黒鉛材の工業的な製造プロセスは、コークス微粉からなるフィラー原料にピッチ系バインダーを配合して混捏する工程、混練物を再粉砕した原料粉を冷間静水圧プレス（ＣＩＰ）により等方的に成形する成形工程、成形体を焼成炭化して等方性高密度組織の炭素成形体を得る焼成工程、および炭素焼成体を黒鉛化処理する黒鉛化工程からなっている。
【０００５】
【発明が解決しようとする課題】
従来の工程によれば、前記成形工程における冷間静水圧プレス（ＣＩＰ）の条件は室温によるものであり、その条件下ではかさ比重、曲げ強度、熱伝導率が低く、電気比抵抗が高いといった問題点があった。
【０００６】
【課題を解決するための手段】
上掲の問題点に関して鋭意研究した結果、下記要旨構成にかかる本発明に想到した。即ち、本発明による黒鉛材の製造方法は、コークス微粉末をフィラー原料とし、該フィラー原料をピッチ系バインダーとともに混捏処理したのち混練物を粉砕し、粉砕粉を静水圧プレスにより５０℃以上２００℃以下の条件下で成形して焼成炭化および黒鉛化処理することを構成上の特徴とする。
すなわち、本発明の課題は下記（１）により達成された。
（１） 平均粒径が２０μｍ以下のコークス微粉末をフィラー原料とし、前記フィラー原料１００重量部に対してピッチ系バインダー３０〜７０重量部とともに混捏処理したのち混練物を前記フィラー原料の平均粒径以上に粉砕し、粉砕粉を静水圧プレスにより５０℃以上２００℃以下の条件下で成形して焼成炭化および黒鉛化処理することを特徴とする黒鉛材の製造方法。
【０００７】
本発明のフィラー原料はコークス微粉末からなる。コークス微粉末としては、石油系またはピッチ系のコークスを２０μｍ以下に粉砕したものが使用される。平均粒径が２０μｍを超えると等方性で緻密質の黒鉛組織が得られなくなる。
【０００８】
上記のフィラー原料は、ピッチ系バインダーと混練処理する。ピッチ系バインダーとしては、コールタール系ピッチまたは石油系ピッチ等が使用される。バインダーの好ましい配合量は、フィラー成分１００重量部に対して３０〜７０重量部の範囲である。バインダー量が３０重量部未満では結合力が不十分となり、７０重量部を超えると焼成後の材質に亀裂や破損を与えるようになる。さらにフィラー原料とバインダーは均一に混練される。
【０００９】
混練物は、適宜な機械的粉砕装置により再粉砕処理して成形粉を作製する。成形粉の平均粒径はフィラー原料の平均粒径と同等以上とする必要がある。この理由は、骨材粒径より細かく粉砕すると表面にバインダー成分が介在しない粒子の割合が高くなり、緻密な材質組織が得られ難くなるためである。
【００１０】
成形粉は、所定のラバーケースに充填し静水圧プレスにより成形する。この際、通常の静水圧プレスでは室温条件下で行われるが、本発明によれば５０℃以上２００℃以下の条件下で行われる。この理由は５０℃未満の条件下の場合、バインダーの粘性が低い為、成形時の圧力伝播が充分に行われず、曲げ強度などの特性が劣化するからであり、２００℃を超える条件下ではバインダーピッチが変質し、接着力がなくなるからである。
【００１１】
得られた成形体は、常法により非酸化性雰囲気下の加熱炉で約１０００℃までの温度で焼成炭化処理して等方性高密度組織の炭素焼成体を得る。ついで、炭素焼成体を黒鉛化炉に詰め、周辺をパッキング材で被包した状態で炉に送電し、所定の昇温速度で２５００℃〜３０００℃まで上昇して黒鉛化処理を施す。
【００１２】
上記の工程で製造される等方性黒鉛材は、かさ比重が１．７５以上、電気比抵抗が１８００μΩｃｍ以下、曲げ強度が４５０ｋｇ／ｃｍ2 以上、熱伝導率が５５ｋｃａｌ／ｍ・ｈｒ・℃以上の範囲にあり、したがって、放電加工用電極などの基材として有用な特性を保有している。
【００１３】
【実施例】
以下、本発明の実施例を比較例と対比して詳細に説明する。
実施例１
フィラー原料として平均粒径１０μｍ、最大粒径５０μｍのコークス粉末を１００重量部、バインダーとしてタールピッチバインダーを４０重量部を配合して捏合機に投入し、２００℃に加熱しながら捏合処理した。混練物を冷却した後、ジェットミル粉砕機により平均粒径５０μｍ、最大粒径１５０μｍに再粉砕して成形粉を得た。この成形粉をラバーに充填して静水圧プレスにセットし、圧力１０００ｋｇ／ｃｍ2 、温度６０℃の条件下にてブロック形状に成形した。ついで、成形体を焼成炉に詰めて非酸化性雰囲気下で約１０００℃の温度で焼成炭化処理し、更に黒鉛化炉に移して非酸化性雰囲気下で約２５００℃の温度により黒鉛化処理した。
【００１４】
得られた等方性黒鉛材の各種特性を測定したところ、かさ比重１．７５、電気比抵抗１７００μΩｃｍ、曲げ強度が６６０ｋｇ／ｃｍ2 以上、熱伝導率が５９ｋｃａｌ／ｍ・ｈｒ・℃であった。
【００１５】
実施例２
実施例１と同様の方法であるが、静水圧プレスの温度条件を９０℃として等方性黒鉛材を製造し、各種特性を測定したところ、かさ比重１．８５、電気比抵抗１６００μΩｃｍ、曲げ強度が７４０ｋｇ／ｃｍ2 以上、熱伝導率が６４ｋｃａｌ／ｍ・ｈｒ・℃であった。
【００１６】
比較例
実施例１と同様の方法であるが、静水圧プレスの温度条件を室温（２０℃）として等方性黒鉛材を製造し、各種特性を測定したところ、かさ比重１．７０、電気比抵抗１９００μΩｃｍ、曲げ強度が４００ｋｇ／ｃｍ2 以上、熱伝導率が５１ｋｃａｌ／ｍ・ｈｒ・℃であった。
【００１７】
【発明の効果】
このように、コークス微粉末をフィラー原料とし、該フィラー原料をピッチ系バインダーとともに混捏処理したのち混練物を粉砕し、粉砕粉を静水圧プレスにより５０℃以上２００℃以下の条件下で成形して焼成炭化および黒鉛化処理することによって、かさ比重、電気比抵抗、曲げ強度、熱伝導率において放電加工用電極などの基材として優れた特性を保有することが可能となる。[0001]
[Industrial application fields]
The present invention is, for example, isotropic of a high-density structure equipped with electrical resistivity, excellent thermal conductivity, etc. suitable as an electrode for electric discharge machining, a crucible for semiconductor production, a member for a single crystal pulling apparatus, a susceptor for CVD, etc. The present invention relates to a method for producing a graphite material.
[0002]
[Prior art]
Isotropic high-density graphite materials are useful as materials such as electrodes for electric discharge machining, crucibles for semiconductor manufacturing, and molds for continuous casting. However, the durability of these products is governed by the characteristics of the graphite material. Therefore, material studies have been made for a long time.
[0003]
For such a graphite material, characteristics such as bulk specific gravity, electrical specific resistance, bending strength, and thermal conductivity have become problems, and recently, the requirements for the material characteristics of the graphite material have become increasingly severe.
[0004]
At present, the industrial production process of isotropic graphite material that is generally used in practice is a process of blending a pitch-based binder with a filler raw material consisting of fine coke powder, and cold-static processing of the raw powder obtained by re-grinding the kneaded product. From a forming step of forming isotropically by a hydraulic press (CIP), a baking step of firing and carbonizing the formed body to obtain a carbon formed body of isotropic high density structure, and a graphitizing step of graphitizing the carbon fired body It has become.
[0005]
[Problems to be solved by the invention]
According to the conventional process, the conditions of the cold isostatic pressing (CIP) in the molding process are based on room temperature, under which the bulk specific gravity, bending strength, thermal conductivity are low, and electrical resistivity is high. There was a problem.
[0006]
[Means for Solving the Problems]
As a result of earnest research on the above-mentioned problems, the present inventors have arrived at the present invention according to the following summary configuration. That is, in the method for producing a graphite material according to the present invention, coke fine powder is used as a filler material, the filler material is kneaded with a pitch-based binder, the kneaded product is pulverized, and the pulverized powder is hydrostatically pressed at 50 ° C. or higher and 200 ° C. It is a structural feature that it is molded and calcined and graphitized under the following conditions.
That is, object of the present invention has been more accomplished in the following (1).
(1) Coke fine powder having an average particle size of 20 μm or less is used as a filler raw material, and after kneading together with 30 to 70 parts by weight of a pitch-based binder with respect to 100 parts by weight of the filler raw material, the kneaded product is an average particle diameter of the filler raw material A method for producing a graphite material, characterized by pulverizing as described above and forming the pulverized powder under a condition of 50 ° C. or higher and 200 ° C. or lower by a hydrostatic pressure press, followed by firing carbonization and graphitization.
[0007]
The filler raw material of this invention consists of coke fine powder. As the fine coke powder, petroleum-based or pitch-based coke pulverized to 20 μm or less is used. When the average particle diameter exceeds 20 μm, an isotropic and dense graphite structure cannot be obtained.
[0008]
The filler material is kneaded with a pitch binder. As the pitch binder, coal tar pitch, petroleum pitch, or the like is used. A preferable blending amount of the binder is in a range of 30 to 70 parts by weight with respect to 100 parts by weight of the filler component. When the amount of the binder is less than 30 parts by weight, the bonding force is insufficient, and when it exceeds 70 parts by weight, the fired material is cracked or broken. Further, the filler raw material and the binder are uniformly kneaded.
[0009]
The kneaded product is re-pulverized by an appropriate mechanical pulverizer to produce a molded powder. The average particle size of the molding powder needs to be equal to or greater than the average particle size of the filler material. The reason for this is that if the particle size is pulverized finer than the aggregate particle size, the proportion of particles having no binder component on the surface increases, making it difficult to obtain a dense material structure.
[0010]
The molding powder is filled in a predetermined rubber case and molded by an isostatic press. At this time, in a normal hydrostatic press, it is performed under room temperature conditions, but according to the present invention, it is performed under conditions of 50 ° C. or more and 200 ° C. or less. The reason for this is that when the temperature is lower than 50 ° C., the viscosity of the binder is low, so that the pressure propagation during molding is not sufficiently performed, and the properties such as bending strength are deteriorated. This is because the pitch is altered and the adhesive force is lost.
[0011]
The obtained molded body is calcined and carbonized at a temperature up to about 1000 ° C. in a heating furnace in a non-oxidizing atmosphere by a conventional method to obtain a carbon fired body having an isotropic high density structure. Next, the carbon fired body is packed in a graphitization furnace, and the periphery is encapsulated with a packing material, and the electric power is transmitted to the furnace, and the temperature is increased to 2500 ° C. to 3000 ° C. at a predetermined temperature increase rate to perform graphitization.
[0012]
The isotropic graphite material produced in the above process has a bulk specific gravity of 1.75 or more, an electrical resistivity of 1800 μΩcm or less, a bending strength of 450 kg / cm 2 or more, and a thermal conductivity of 55 kcal / m · hr · ° C. or more. Therefore, it has characteristics useful as a substrate such as an electrode for electric discharge machining.
[0013]
【Example】
Hereinafter, examples of the present invention will be described in detail in comparison with comparative examples.
Example 1
100 parts by weight of coke powder having an average particle diameter of 10 μm and a maximum particle diameter of 50 μm as a filler material and 40 parts by weight of a tar pitch binder as a binder were mixed and charged into a compounding machine. After the kneaded product was cooled, it was reground to an average particle size of 50 μm and a maximum particle size of 150 μm with a jet mill grinder to obtain a molding powder. The molding powder was filled into a rubber and set in a hydrostatic press, and molded into a block shape under the conditions of a pressure of 1000 kg / cm 2 and a temperature of 60 ° C. Next, the compact was packed in a firing furnace and calcined at a temperature of about 1000 ° C. in a non-oxidizing atmosphere, and further transferred to a graphitization furnace and graphitized at a temperature of about 2500 ° C. in a non-oxidizing atmosphere. .
[0014]
When various characteristics of the obtained isotropic graphite material were measured, the bulk specific gravity was 1.75, the electrical specific resistance was 1700 μΩcm, the bending strength was 660 kg / cm 2 or more, and the thermal conductivity was 59 kcal / m · hr · ° C. .
[0015]
Example 2
The method is the same as in Example 1, but the isotropic graphite material was manufactured at a hydrostatic pressure temperature of 90 ° C. and various properties were measured. The bulk specific gravity was 1.85, the electrical resistivity was 1600 μΩcm, the bending strength. Was 740 kg / cm 2 or more, and the thermal conductivity was 64 kcal / m · hr · ° C.
[0016]
Comparative Example The same method as in Example 1, except that an isotropic graphite material was produced at a hydrostatic pressure temperature of room temperature (20 ° C.) and various properties were measured. The resistance was 1900 μΩcm, the bending strength was 400 kg / cm 2 or more, and the thermal conductivity was 51 kcal / m · hr · ° C.
[0017]
【The invention's effect】
As described above, coke fine powder is used as a filler raw material, the filler raw material is kneaded with a pitch-based binder, the kneaded product is pulverized, and the pulverized powder is molded under conditions of 50 ° C. or higher and 200 ° C. or lower by an isostatic press. By performing the firing carbonization and graphitization treatment, it is possible to have excellent characteristics as a base material such as an electrode for electric discharge machining in terms of bulk specific gravity, electrical specific resistance, bending strength, and thermal conductivity.
Claims (1)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP19672098A JP4311777B2 (en) | 1998-06-26 | 1998-06-26 | Method for producing graphite material |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP19672098A JP4311777B2 (en) | 1998-06-26 | 1998-06-26 | Method for producing graphite material |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2000007436A JP2000007436A (en) | 2000-01-11 |
| JP4311777B2 true JP4311777B2 (en) | 2009-08-12 |
Family
ID=16362484
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP19672098A Expired - Lifetime JP4311777B2 (en) | 1998-06-26 | 1998-06-26 | Method for producing graphite material |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP4311777B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR101577129B1 (en) * | 2013-03-05 | 2015-12-11 | 이비덴 가부시키가이샤 | A method of producing graphite material |
Families Citing this family (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP5520564B2 (en) | 2009-10-13 | 2014-06-11 | 東洋炭素株式会社 | Carbon material and manufacturing method thereof |
| JP2014144913A (en) * | 2014-04-04 | 2014-08-14 | Toyo Tanso Kk | Carbon material |
| CN115403383A (en) * | 2021-05-28 | 2022-11-29 | 成都炭素有限责任公司 | Manufacturing method of graphite mold material for hot bending of curved-surface glass |
| CN113831126A (en) * | 2021-09-17 | 2021-12-24 | 大同新成新材料股份有限公司 | Preparation method of isostatic pressing negative electrode carbon material |
| CN113912397A (en) * | 2021-09-17 | 2022-01-11 | 大同新成新材料股份有限公司 | Method for producing isostatic graphite product by using isostatic pressing roasting waste products |
| CN114591083A (en) * | 2022-03-02 | 2022-06-07 | 五星新材科技有限公司 | Isotropic isostatic pressing graphite sealing material and preparation method thereof |
| CN114853484B (en) * | 2022-05-20 | 2023-04-28 | 四川士达特种炭材有限公司 | One-time roasting method for isostatic pressing graphite cylinder material |
| CN116462509B (en) * | 2023-05-04 | 2023-11-07 | 湖北东南佳特碳新材料有限公司 | Isostatic pressure graphite for photovoltaic and preparation method and application thereof |
-
1998
- 1998-06-26 JP JP19672098A patent/JP4311777B2/en not_active Expired - Lifetime
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR101577129B1 (en) * | 2013-03-05 | 2015-12-11 | 이비덴 가부시키가이샤 | A method of producing graphite material |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2000007436A (en) | 2000-01-11 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US7658902B2 (en) | Low CTE highly isotropic graphite | |
| JP4311777B2 (en) | Method for producing graphite material | |
| JP3765840B2 (en) | Carbon material manufacturing method | |
| JP4430448B2 (en) | Method for producing isotropic graphite material | |
| JPH07165467A (en) | Production of isotropic graphite material | |
| EP0146399A2 (en) | Nuclear graphite articles and their production | |
| JPH0234508A (en) | Preparation of isotropic carbon material having high density | |
| JPH0259468A (en) | Production of isotropic graphite material modified to have high specific resistance | |
| JP2001130963A (en) | Method for producing isotropic high-density carbon material | |
| JP2005008436A (en) | Graphite material, method for producing the same, and fuel cell separator | |
| JPH0132162B2 (en) | ||
| JPS6096573A (en) | Pitch-free graphite product and manufacture | |
| US9546113B2 (en) | High porosity/low permeability graphite bodies and process for the production thereof | |
| JP4107038B2 (en) | Process for producing calcined coke | |
| JP7357286B2 (en) | Method for producing graphite material with high coefficient of thermal expansion and its graphite material | |
| JPH04321560A (en) | Production of isotropic graphite material having high strength | |
| JP3198123B2 (en) | Method for producing isotropic high-strength graphite material | |
| JP2808807B2 (en) | Production method of raw material powder for carbon material | |
| JPS6291412A (en) | Method for charging isotropic carbon molded body to baking furnace | |
| JP2924061B2 (en) | Production method of raw material powder for carbon material | |
| JPH06122552A (en) | Production of isotropic high-density graphite material | |
| JPH0764528B2 (en) | Method for producing high-quality carbonaceous compact | |
| JP2924062B2 (en) | Production method of raw material powder for carbon material | |
| JP3591784B2 (en) | Graphitization method of high density carbon fired body | |
| SU1034994A1 (en) | Method for preparing coke and pitch composition for making fine-grained graphite products |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20050525 |
|
| A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20080206 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20080507 |
|
| RD03 | Notification of appointment of power of attorney |
Free format text: JAPANESE INTERMEDIATE CODE: A7423 Effective date: 20080627 |
|
| A521 | Written amendment |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20080707 |
|
| A521 | Written amendment |
Free format text: JAPANESE INTERMEDIATE CODE: A821 Effective date: 20080627 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20081022 |
|
| A521 | Written amendment |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20081219 |
|
| TRDD | Decision of grant or rejection written | ||
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20090428 |
|
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 |
|
| A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20090512 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20120522 Year of fee payment: 3 |
|
| R150 | Certificate of patent or registration of utility model |
Free format text: JAPANESE INTERMEDIATE CODE: R150 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20120522 Year of fee payment: 3 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20130522 Year of fee payment: 4 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20140522 Year of fee payment: 5 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| EXPY | Cancellation because of completion of term |